Crankcase lubricant compositions may be selected to provide an increased engine protection while providing an increase in fuel economy and reduced emissions. However, in order to achieve benefits of improved fuel economy and reduced emissions, a balance between engine protection and lubricating properties is required for the lubricant composition. For example, an increase in the amount of friction modifiers may be beneficial for fuel economy purposes but may lead to reduced ability of the lubricant composition to handle water. Likewise, an increase in the amount of anti-wear agent in the lubricant may provide improved engine protection against wear but may be detrimental to catalyst performance for reducing emissions. Accordingly, there is a need for improved lubricant compositions that are suitable for meeting or exceeding currently proposed and future lubricant performance standards.
With regard to the foregoing, embodiments of the disclosure provide a crankcase lubricant composition, method for improving the soot or sludge handling capability of a crankcase lubricant composition and a method of operating an engine on a crankcase lubricant composition. The lubricant composition includes a base oil and a reaction product of mono-succinimide dispersant and an acidic compound containing two or more pyrrole groups.
An embodiment of the disclosure provides a method for improving the soot or sludge handling capability of a crankcase lubricant for an engine composition. The method includes formulating a lubricant composition for the engine with a base oil and a reaction product of a monosuccinimide dispersant and an acidic compound containing at least two pyrrole groups. The engine is operated with the crankcase lubricant to provide the improved soot and sludge handling capabilities.
A further embodiment of the disclosure provides a method for operating an engine. The method includes formulating a crankcase lubricant for the engine having a base oil and a lubricant additive package including a reaction product of a monosuccinimide dispersant and an acidic compound containing at least two pyrrole groups. The engine is operated with the crankcase lubricant.
Another embodiment of the disclosure provides a dispersant for a crankcase lubricant comprising a reaction product of monosuccinimide dispersant and an acidic compound containing at least two pyrrole groups.
An unexpected advantage of the use of a dispersant derivative provides improved soot or sludge handling capabilities to a lubricant. Such capabilities may be achieved with substantially less dispersant compared to a lubricant composition containing a conventional dispersant. A further advantage of the use of the dispersant derivative described herein is that since less dispersant is required to achieve comparable soot or sludge handling capabilities, lubricant compositions containing the dispersant may have greater seal compatibility and lower lead corrosion.
The following definitions of terms are provided in order to clarify the meanings of certain terms as used herein.
As used herein, the terms “oil composition,” “lubrication composition,” “lubricating oil composition,” “lubricating oil,” “lubricant composition,” “lubricating composition,” “fully formulated lubricant composition,” and “lubricant” are considered synonymous, fully interchangeable terminology referring to the finished lubrication product comprising a major amount of a base oil plus a minor amount of an additive composition.
As used herein, the terms “additive package,” “additive concentrate,” and “additive composition” are considered synonymous, fully interchangeable terminology referring the portion of the lubricating composition excluding the major amount of base oil stock mixture.
As used herein, the term “hydrocarbyl substituent” or “hydrocarbyl group” is used in its ordinary sense, which is well-known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character. Examples of hydrocarbyl groups include:                (1) hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic-, and alicyclic-substituted aromatic substituents, as well as cyclic substituents wherein the ring is completed through another portion of the molecule (e.g., two substituents together form an alicyclic radical);        (2) substituted hydrocarbon substituents, that is, substituents containing non-hydrocarbon groups which, in the context of this invention, do not alter the predominantly hydrocarbon substituent (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy);        (3) hetero substituents, that is, substituents which, while having a predominantly hydrocarbon character, in the context of this invention, contain other than carbon in a ring or chain otherwise composed of carbon atoms. Heteroatoms include sulfur, oxygen, nitrogen, and encompass substituents such as pyridyl, furyl, thienyl, and imidazolyl. In general, no more than two, for example, no more than one, non-hydrocarbon substituent will be present for every ten carbon atoms in the hydrocarbyl group; typically, there will be no non-hydrocarbon substituents in the hydrocarbyl group.        
As used herein, the term “percent by weight”, unless expressly stated otherwise, means the percentage the recited component represents to the weight of the entire composition.
The terms “oil-soluble” or “dispersible” used herein do not necessarily indicate that the compounds or additives are soluble, dissolvable, miscible, or capable of being suspended in the oil in all proportions. The foregoing terms do mean, however, that they are, for instance, soluble or stably dispersible in oil to an extent sufficient to exert their intended effect in the environment in which the oil is employed. Moreover, the additional incorporation of other additives may also permit incorporation of higher levels of a particular additive, if desired.
Crankcase lubricating oils of the present disclosure may be formulated by the addition of one or more additives, as described in detail below, to an appropriate base oil formulation. The additives may be combined with a base oil in the form of an additive package (or concentrate) or, alternatively, may be combined individually with a base oil. The fully formulated crankcase lubricant may exhibit improved performance properties, based on the additives added and their respective proportions.
Additional details and advantages of the disclosure will be set forth in part in the description which follows, and/or may be learned by practice of the disclosure. The details and advantages of the disclosure may be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure, as claimed.